The present invention generally relates to a humidifier. More particularly, the present invention relates to a compact gas humidifying device having a long flow path and packing materials.
There are a variety of devices used to humidify gases in domestic applications and industrial applications. Examples of known humidifying devices include bubbler humidifiers, packed column humidifiers, membrane humidifiers, etc.
One known type of humidifier uses water injection to humidify the gas. The humidifier has a generally hollow cylindrical body and a plurality of water injection nozzles for injecting water into the hollow cylindrical body. The water injection nozzles are typically provided on one side wall of the hollow cylindrical body. Dry gas enters the humidifier through a gas inlet provided at one end of the hollow cylindrical body and flows along the axial direction of the hollow cylindrical body to the opposite end. As the gas flows through the hollow cylindrical body water is injected into the hollow of the body through the plurality of injection nozzles, humidifying the gas. The humidified gas then leaves the hollow cylindrical body through a gas outlet provided at the opposite end of the hollow cylindrical body. The flow path of the gas is relatively short with little contact area between the gas and the water. In order to increase the flow path and contact area between the gas and the water the device tends to be large.
Another known type of humidifier uses a packing material to increase the contact area between the gas and the water. Examples of this type of humidifier have been disclosed in U.S. Pat. Nos. 3,983,190 and 5,769,067. The humidifier has a generally hollow cylindrical body and is disposed in a substantially vertical position. The gas enters the hollow cylindrical body from a gas inlet provided on a bottom wall of the hollow cylindrical body, and is forced to flow upwardly along the axial direction of the hollow cylindrical body by a blower or fan. A water inlet is provided on a top wall of the hollow cylindrical body to dispense water to a water distribution plate that is disposed within the hollow cylindrical body generally parallel to and near the top wall. A plurality of holes are provided in the water distribution plate so that water coming from the water inlet can drip down through the holes to humidify the gas flowing upwardly through the hollow cylindrical body. A packing material can be packed between the water distribution plate and the bottom wall to increase the contact area between the gas and the water.
A humidifier employing a water permeable membrane is disclosed in U.S. Pat. No. 5,348,691. Passages for the gas to be humidified and passages for water are provided on opposite sides of a membrane. As the gas flows along the passages on one side of the membrane water, flowing through the passages on the other side of the membrane, permeates through the membrane to humidify the gas.
In accordance with the present invention, a humidifier is provided having a housing defining a chamber. The housing is provided with a gas inlet to the chamber and a gas outlet from the chamber and at least one fluid distributing portion connected to the housing to distribute a fluid within the chamber. At least one baffle is disposed within the chamber to define a flow path for the gas between the gas inlet and the gas outlet. The present invention is described using humidifying air with water as an example. It can be appreciated, however, that the present invention can also be used to humidify other gases or fluids and to exchange heat.
In one embodiment the at least one baffle comprises a plurality of baffles plates. In particular, the baffle plates are disposed within the chamber generally transverse to the fluid distributing portion and spaced from one another over a longitudinal extent of the fluid distributing portion. The extent of the baffle plates in the direction generally transverse to the fluid distributing portion is sufficient to define within the chamber gas flow paths adjacent the baffle plates. Each baffle plate can have a top edge and a bottom edge and a width, with the width being substantially the same as the width of the side walls of the chamber, that is to say, for the embodiment disclosed, the baffle plates extend from one side wall of the chamber to the other side wall. The baffle plates can be of various shapes and it is not necessary that the baffle plates be similar in shape and dimension to each other. For the embodiment disclosed the baffle plates have generally the same shape and dimension.
Each baffle plate is provided with an opening to allow gas to flow between adjacent flow paths. The opening of a given baffle plate is at an end of the baffle plate that is opposed to the end of where an opening of an adjacent baffle plate is provided.
In the embodiment disclosed the opening is provided by spacing an end of the baffle plate from at least one of the fluid distributing portions and the inner walls of the chamber. Moreover, adjacent baffle plates are positioned within the chamber so as to be offset with respect to one another in a direction generally transverse to the fluid distributing portion. This presents the opening of a given baffle plate in opposition to where an opening of an adjacent baffle plate is provided.
Moreover, at least some of the baffle plates can be provided with an aperture to allow fluid to flow between adjacent flow paths.
Further, the baffle plates can be disposed within the chamber at generally 90xc2x0 to the fluid distributing portion.
The chamber of the humidifier can also be contain a packing material, such as, for example, metal chips, plastic chips, or any other suitable random or structured packing material. The packing material can fill two thirds of the chamber of the housing.
Further, at least one port can be provided to connect the fluid distributing portion to an external fluid source. At least one fluid distributing port can also be provided to distribute the fluid to the chamber, and a at least one fluid passage to connect the ports to the fluid distributing ports. The fluid distributing ports can be provided with fluid spraying nozzles. A fluid level sensor to monitor the fluid level in the chamber can also be provided.
The housing is open at least one end and the fluid distributing portion is disposed within the open end of the housing. In one embodiment the housing is disposed so that the at least one open end faces upwardly. In another embodiment the housing is disposed so that at least one open end faces a side thereof. In yet a further embodiment the housing is disposed so that one open end faces one side thereof and a another open end faces an opposed side thereof. For each of these embodiments the water distributing portion can be disposed over the open end of the housing.
Further the housing and the fluid distributing portion can be generally rectangular in shape. Similarly the chamber can be generally rectangular in shape. The gas inlet and the gas outlet can be provided at opposite ends of the housing.
For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made to the accompanying drawings, which show, by way of example, preferred embodiments of the present invention.